Nautel Vector-LP VR125 - Page 12

Vector-LP Radio Beacon Transmitter Technical Instruction Manual Feb.24.09
Contents Page
5 MAINTENANCE AND TROUBLESHOOTING
5.1 GENERAL 5-1
5.2 SCHEDULED MAINTENANCE 5-1
5.3 CORRECTIVE MAINTENANCE 5-2
5.4 ELECTROSTATIC PROTECTION 5-2
5.5 TROUBLESHOOTING FRONT PANEL ALARMS 5-3
5.6 REPLACING AN RF POWER MODULE 5-9
5.7 FET CHECKING/REPLACEMENT 5-11
5.8 EXCITER PANEL PWB REPLACEMENT 5-12
5.8.1 Exciter Interface PWB and Interconnecting PWB
Replacement 5-12
5.8.2 Exciter Monitor/Generator PWB Replacement 5-13
5.8.3 Interface PWB Replacement 5-14
5.9 BATTERY BOOST ASSEMBLY REPLACEMENT 5-14
6 THEORY OF OPERATION
6.1 INTRODUCTION 6-1
6.2 TRANSMITTER OVERVIEW 6-1
6.3 AC_DC POWER STAGE 6-1
6.3.1 Interface PWB 6-5
6.3.2 Ac/Dc Universal Input Power Supplies 6-5
6.4 EXCITER STAGE 6-6
6.4.1 Exciter Interface PWB 6-6
6.4.2 RF Synthesizer PWBs 6-6
6.4.3 Interphase PDM Driver PWBs 6-8
6.4.4 Exciter Monitor/Generator PWBs 6-15
6.5 CONTROL/MONITOR STAGE 6-16
6.5.1 Control/Display PWB 6-16
6.5.2 Remote Interface PWB 6-19
6.5.3 Front Panel Metering 6-20
6.5.4 NDB Site Interface PWB (Optional) 6-21
6.5.5 Modem (Optional) 6-21
6.6 RF POWER STAGE 6-22
6.6.1 RF Power Module(s) 6-22
6.6.2 RF Filter PWB 6-29
6.6.3 RF Power Probe PWB 6-29
6.7 MODULATION DEPTH WHEN USING A HIGH ‘Q’
ANTENNA 6-30